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AIMS/HYPOTHESIS: The aim of this study was to evaluate the efficacy and safety of oral semaglutide monotherapy vs placebo in a predominantly Chinese population with type 2 diabetes insufficiently controlled with diet and exercise alone. METHODS: The Peptide Innovation for Early Diabetes Treatment (PIONEER) 11 trial was a double-blind, randomised, Phase IIIa trial conducted across 52 sites in the China region (mainland China and Taiwan), Hungary, Serbia and Ukraine. Eligible participants were ≥18 years (≥20 years in Taiwan), had a diagnosis of type 2 diabetes with HbA1c 53-86 mmol/mol (7.0-10.0%) and were not receiving any glucose-lowering drugs. After a 4-week run-in period in which participants were treated with diet and exercise alone, those who fulfilled the randomisation criteria were randomised (1:1:1:1) using a web-based randomisation system to receive once-daily oral semaglutide 3 mg, 7 mg or 14 mg or placebo for 26 weeks (using a 4-week dose-escalation regimen for the higher doses). Randomisation was stratified according to whether participants were from the China region or elsewhere. The primary and confirmatory secondary endpoints were change from baseline to week 26 in HbA1c and body weight (kg), respectively. Safety was assessed in all participants exposed to at least one dose of the trial product. RESULTS: Between October 2019 and October 2021, a total of 774 participants were screened and 521 participants were randomised to oral semaglutide 3 mg (n=130), 7 mg (n=130), 14 mg (n=130) or placebo (n=131); most participants (92.5%, n=482) completed the trial, with 39 participants prematurely discontinuing treatment. The number of participants contributing to the trial analyses was based on the total number of participants who were randomised at the beginning of the trial. The majority of participants were male (63.7%), and the mean age of participants was 52 years. At baseline, mean HbA1c and body weight were 63 mmol/mol (8.0%) and 79.6 kg, respectively. Oral semaglutide resulted in significantly greater reductions in HbA1c than placebo at week 26 (p<0.001 for all doses). The estimated treatment differences (ETDs [95% CIs]) for oral semaglutide 3 mg, 7 mg and 14 mg vs placebo were -11 (-13, -9) mmol/mol, -16 (-18, -13) mmol/mol and -17 (-19, -15) mmol/mol, respectively. The corresponding ETDs in percentage points (95% CI) vs placebo were -1.0 (-1.2, -0.8), -1.4 (-1.6, -1.2) and -1.5 (-1.8, -1.3), respectively. Significantly greater reductions in body weight were also observed for oral semaglutide 7 mg and 14 mg than for placebo at week 26 (ETD [95% CI] -1.2 kg [-2.0 kg, -0.4 kg; p<0.01] and -2.0 kg [-2.8 kg, -1.2 kg; p<0.001], respectively), but not for oral semaglutide 3 mg (ETD [95% CI] -0.0 kg [-0.9 kg, 0.8 kg; not significant]). Similar reductions in HbA1c and body weight were observed in the Chinese subpopulation, which represented 74.9% of participants in the overall population. Adverse events (AEs) occurred in between 65.4% and 72.3% of participants receiving oral semaglutide (for all doses) and 57.3% of participants with placebo. Most AEs were mild to moderate in severity, with few serious AEs reported; the most commonly reported AEs were gastrointestinal-related and were more frequent with semaglutide (all doses) than with placebo. The proportion of AEs was slightly higher in the Chinese subpopulation. CONCLUSIONS/INTERPRETATION: Oral semaglutide resulted in significantly greater reductions in HbA1c across all doses and in significant body weight reductions for the 7 mg and 14 mg doses when compared with placebo in predominantly Chinese participants with type 2 diabetes insufficiently controlled by diet and exercise alone. Oral semaglutide was generally well tolerated, with a safety profile consistent with that seen in the global PIONEER trials. TRIAL REGISTRATION: ClinicalTrials.gov NCT04109547. FUNDING: Novo Nordisk A/S.
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AIMS/HYPOTHESIS: The aim of this study was to assess the efficacy and safety of oral semaglutide vs sitagliptin in a predominantly Chinese population with type 2 diabetes inadequately controlled with metformin treatment. METHODS: The Peptide Innovation for Early Diabetes Treatment (PIONEER) 12 trial was a randomised, double-dummy, active-controlled, parallel-group, Phase IIIa trial conducted over 26 weeks at 90 sites across the China region (including mainland China, Taiwan and Hong Kong) and five other countries. Adults aged ≥18 years (≥20 years in Taiwan) with a diagnosis of type 2 diabetes, HbA1c between 53 and 91 mmol/mol (inclusive) and treated with a stable daily dose of metformin were eligible for inclusion. Participants were randomised (1:1:1:1) using a web-based randomisation system to either once-daily oral semaglutide (3 mg, 7 mg or 14 mg) or once-daily oral sitagliptin 100 mg. Treatment allocation was masked to both participants and investigators. Randomisation was stratified according to whether participants were from the China region or elsewhere. The primary endpoint was change in HbA1c from baseline to week 26. The confirmatory secondary endpoint was change in body weight (kg) from baseline to week 26. All randomised participants were included in the full analysis set (FAS). All participants exposed to at least one dose of trial product were included in the safety analysis (SAS). RESULTS: Of 1839 participants screened, 1441 were randomly assigned to oral semaglutide 3 mg (n=361), 7 mg (n=360), 14 mg (n=361) or sitagliptin 100 mg (n=359) and included in the FAS. A total of 1438 participants were included in the SAS. In total, 75.2% of participants were from the China region. A total of 1372 (95.2%) participants completed the trial and 130 participants prematurely discontinued treatment (8.3%, 8.6% and 15.0% for oral semaglutide 3 mg, 7 mg and 14 mg, respectively; 4.2% for sitagliptin 100 mg). Significantly greater reductions in HbA1c from baseline to week 26 were reported for all doses of oral semaglutide vs sitagliptin 100 mg. For oral semaglutide 3 mg, 7 mg and 14 mg vs sitagliptin 100 mg, the estimated treatment differences (ETDs [95% CI]) were -2 (-4, -1) mmol/mol, -8 (-9, -6) mmol/mol and -11 (-12, -9) mmol/mol, respectively. The corresponding ETDs (95% CI) in percentage points vs sitagliptin 100 mg were -0.2 (-0.3, -0.1), -0.7 (-0.8, -0.6) and -1.0 (-1.1, -0.8), respectively. Reductions in body weight were significantly greater for all doses of oral semaglutide vs sitagliptin 100 mg (ETD [95% CI] -0.9 [-1.4, -0.4] kg, -2.3 [-2.8, -1.8] kg and -3.3 [-3.8, -2.8] kg for 3 mg, 7 mg and 14 mg, respectively). In the subpopulation of participants from the China region (75.2% of trial participants), reductions in HbA1c and body weight from baseline to week 26 were similar to those seen in the overall population. The most frequent adverse events in the semaglutide treatment arms were gastrointestinal, although these were mostly transient and mild/moderate in severity. CONCLUSIONS/INTERPRETATION: Significantly greater reductions in both HbA1c and body weight over 26 weeks were seen with oral semaglutide 3 mg, 7 mg and 14 mg than with sitagliptin 100 mg in a predominantly Chinese population with type 2 diabetes inadequately controlled with metformin treatment. Oral semaglutide was generally well tolerated, with a safety profile consistent with that seen in the global PIONEER trials. TRIAL REGISTRATION: ClinicalTrials.gov NCT04017832. FUNDING: This trial was funded by Novo Nordisk A/S, Søborg, Denmark.
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BACKGROUND: Once-daily oral semaglutide is an effective type 2 diabetes treatment. We aimed to investigate a new formulation of oral semaglutide at higher investigational doses versus the approved 14 mg dose in adults with inadequately controlled type 2 diabetes. METHODS: This global, multicentre, randomised, double-blind, phase 3b trial, carried out at 177 sites in 14 countries, enrolled adults with type 2 diabetes, glycated haemoglobin (HbA1c) 8·0-10·5% (64-91 mmol/mol), a BMI of 25·0 kg/m2 or greater, receiving stable daily doses of one to three oral glucose-lowering drugs. Participants were randomly assigned (1:1:1), by means of an interactive web response system, to once-daily oral semaglutide 14 mg, 25 mg, or 50 mg for 68 weeks. Investigators, site personnel, trial participants, and trial sponsor staff were masked to dose assignment throughout the trial. The primary endpoint was change in HbA1c from baseline to week 52, evaluated with a treatment policy estimand in the intention-to-treat population. Safety was assessed in all participants who received at least one dose of trial drug. This trial is registered with ClinicalTrials.gov, NCT04707469, and the European Clinical Trials register, EudraCT 2020-000299-39, and is complete. FINDINGS: Between Jan 15 and Sept 29, 2021, of 2294 people screened, 1606 (n=936 [58·3%] male; n=670 [41·7%] female; mean [SD] age 58·2 [10·8] years) received oral semaglutide 14 mg (n=536), 25 mg (n=535), or 50 mg (n=535). At baseline, mean (SD) HbA1c was 9·0% (0·8; 74·4 mmol/L [SD 8·3]) and mean bodyweight was 96·4 kg (21·6). Mean changes (SE) in HbA1c at week 52 were -1·5 percentage points (SE 0·05) with oral semaglutide 14 mg, -1·8 percentage points (0·06) with 25 mg (estimated treatment difference [ETD] -0·27, 95% CI -0·42 to -0·12; p=0·0006), and -2·0 percentage points (0·06) with 50 mg (ETD -0·53, -0·68 to -0·38; p<0·0001). Adverse events were reported by 404 (76%) participants in the oral semaglutide 14 mg group, 422 (79%) in the 25 mg group, and 428 (80%) in the 50 mg group. Gastrointestinal disorders, which were mostly mild to moderate, occurred more frequently with oral semaglutide 25 mg and 50 mg than with 14 mg. Ten deaths occurred during the trial; none were judged to be treatment related. INTERPRETATION: Oral semaglutide 25 mg and 50 mg were superior to 14 mg in reducing HbA1c and bodyweight in adults with inadequately controlled type 2 diabetes. No new safety concerns were identified. FUNDING: Novo Nordisk.
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Diabetes Mellitus Tipo 2 , Humanos , Masculino , Adulto , Feminino , Pessoa de Meia-Idade , Diabetes Mellitus Tipo 2/tratamento farmacológico , Hipoglicemiantes/uso terapêutico , Peptídeos Semelhantes ao Glucagon , Resultado do Tratamento , Método Duplo-Cego , Peso CorporalRESUMO
BACKGROUND: Early non-motor features including anxiety, depression and altered social cognition are present in Huntington's disease (HD). The underlying neurobiological mechanisms are not known. Oxytocin (OXT) is involved in the regulation of emotion, social cognition and metabolism, and our previous work showed that the OXT system is affected early in HD. The aim of the study was to investigate the potential causal relationship between the selective expression of mutant huntingtin (mHTT) in OXT neurons and the development of non-motor features and neuropathology. METHODS: To express mHTT only in OXT neurons, we used a novel flex-switch adeno-associated viral vector design to selectively express either mHTT or wild-type HTT in the paraventricular nucleus of the hypothalamus using OXT-Cre-recombinase mice. We also performed a mirror experiment to selectively delete mHTT in OXT neurons using the BACHD mouse model. Mice underwent a battery of behavioural tests to assess psychiatric and social behaviours 3 months post-injection or at 2 months of age, respectively. Post-mortem analyses were performed to assess the effects on the OXT system. RESULTS: Our results show that selective expression of mHTT in OXT neurons was associated with the formation of mHTT inclusions and a 26% reduction of OXT-immunopositive neurons as well as increased anxiety-like behaviours compared with uninjected mice. However, selective deletion of mHTT from OXT neurons alone was not sufficient to alter the metabolic and psychiatric phenotype of the BACHD mice at this early time point. CONCLUSIONS: Our results indicate that mHTT expression can exert cell-autonomous toxic effects on OXT neurons without affecting the non-motor phenotype at early time points in mice.
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Doença de Huntington , Camundongos , Animais , Doença de Huntington/metabolismo , Ocitocina/metabolismo , Fenótipo , Neurônios/patologia , Proteína Huntingtina/genética , Modelos Animais de Doenças , Camundongos TransgênicosRESUMO
AIMS: To determine the underlying cellular changes and clinical correlates associated with pathology of the hypothalamus in amyotrophic lateral sclerosis (ALS), as hypothalamic atrophy occurs in the preclinical phase of the disease. METHODS: The hypothalamus was pathologically examined in nine patients with amyotrophic lateral sclerosis in comparison to eight healthy control subjects. The severity of regional atrophy (paraventricular nucleus: PVN, fornix and total hypothalamus) and peptidergic neuronal loss (oxytocin, vasopressin, cocaine- and amphetamine-regulating transcript: CART, and orexin) was correlated with changes in eating behaviour, sleep function, cognition, behaviour and disease progression. RESULTS: Tar DNA-binding protein 43 (TDP-43) inclusions were present in the hypothalamus of all patients with amyotrophic lateral sclerosis. When compared to controls, there was atrophy of the hypothalamus (average 21% atrophy, p = 0.004), PVN (average 30% atrophy p = 0.014) and a loss of paraventricular oxytocin-producing neurons (average 49% loss p = 0.02) and lateral hypothalamic orexin-producing neurons (average 37% loss, significance p = 0.02). Factor analysis identified strong relationships between abnormal eating behaviour, hypothalamic atrophy and loss of orexin-producing neurons. With increasing disease progression, abnormal sleep behaviour and cognition associated with atrophy of the fornix. CONCLUSIONS: Substantial loss of hypothalamic oxytocin-producing neurons occurs in ALS, with regional atrophy and the loss of orexin neurons relating to abnormal eating behaviour in ALS. Oxytocin- and orexin neurons display TDP43 inclusions. Our study points to significant pathology in the hypothalamus that may play a key role in metabolic and pathogenic changes in ALS.
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Esclerose Lateral Amiotrófica/metabolismo , Hipotálamo/metabolismo , Orexinas/metabolismo , Ocitocina/metabolismo , Sono/fisiologia , Idoso , Idoso de 80 Anos ou mais , Esclerose Lateral Amiotrófica/patologia , Atrofia/patologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Neurônios/patologiaRESUMO
CONTEXT: White matter lesions (WML) are caused by obstruction of small cerebral vessels associated with stroke risk. Craniopharyngioma (CP) patients suffer from increased cerebrovascular mortality. OBJECTIVE: To investigate the effect of reduced HT volume and cranial radiotherapy (CRT) on WML in childhood-onset CP patients. DESIGN: A cross-sectional study of 41 patients (24 women) surgically treated childhood-onset CP in comparison to controls. SETTING: The South Medical Region of Sweden (2.5 million inhabitants). METHODS: With magnetic resonance imaging (MRI), we analysed qualitative measurement of WML based on the visual rating scale of Fazekas and quantitative automated segmentation of WML lesion. Also, measurement HT volume and of cardiovascular risk factors were analysed. RESULTS: Patients had a significant increase in WML volume (mL) (P = .001) compared to controls. Treatment with cranial radiotherapy (CRT) vs no CRT was associated with increased WML volume (P = .02) as well as higher Fazekas score (P = .001). WML volume increased with years after CRT (r = 0.39; P = .02), even after adjustment for fat mass and age. A reduced HT volume was associated with increased WML volume (r = -0.61, P < .001) and explained 26% of the variation (r2 = 0.26). Altogether, 47% of the WML volume was explained by age at investigation, HT volume and CRT. Patients with more WML also had higher cardiovascular risk. CONCLUSIONS: CRT may be associated directly with increased WML volume or indirectly with reduced HT volume associated with higher cardiovascular risk. Risk factors should be carefully monitored in these patients.
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Craniofaringioma , Neoplasias Hipofisárias , Substância Branca , Encéfalo , Craniofaringioma/radioterapia , Estudos Transversais , Feminino , Humanos , Imageamento por Ressonância Magnética , Neoplasias Hipofisárias/radioterapia , Substância Branca/diagnóstico por imagemRESUMO
Huntington disease (HD) is a fatal neurodegenerative disorder caused by an expanded CAG repeat in the huntingtin (HTT) gene. The typical motor symptoms have been associated with basal ganglia pathology. However, psychiatric and cognitive symptoms often precede the motor component and may be due to changes in the limbic system. Recent work has indicated pathology in the hypothalamus in HD but other parts of the limbic system have not been extensively studied. Emerging evidence suggests that changes in HD also include white matter pathology. Here we investigated if the main white matter tract of the limbic system, the fornix, is affected in HD. We demonstrate that the fornix is 34% smaller already in prodromal HD and 41% smaller in manifest HD compared to controls using volumetric analyses of MRI of the IMAGE-HD study. In post-mortem fornix tissue from HD cases, we confirm the smaller fornix volume in HD which is accompanied by signs of myelin breakdown and reduced levels of the transcription factor myelin regulating factor but detect no loss of oligodendrocytes. Further analyses using RNA-sequencing demonstrate downregulation of oligodendrocyte identity markers in the fornix of HD cases. Analysis of differentially expressed genes based on transcription-factor/target-gene interactions also revealed enrichment for binding sites of SUZ12 and EZH2, components of the Polycomb Repressive Complex 2, as well as RE1 Regulation Transcription Factor. Taken together, our data show that there is early white matter pathology of the fornix in the limbic system in HD likely due to a combination of reduction in oligodendrocyte genes and myelin break down.
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Fórnice/patologia , Doença de Huntington/patologia , Sistema Límbico/patologia , Substância Branca/patologia , Adulto , Idoso , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Bainha de Mielina/patologia , Oligodendroglia/patologiaRESUMO
OBJECTIVE: Metabolic complications are frequent in childhood leukaemia (ALL) survivors treated with cranial radiotherapy (CRT). These complications are potentially mediated by damage to the hypothalamus (HT), as childhood onset (CO) craniopharyngioma (CP) survivors without HT involvement are spared overt obesity. Diffusion tensor imaging (DTI) shows brain tissue microstructure alterations, by fractional anisotrophy (FA), mean diffusivity (MD), axial diffusivity (AD) and radial diffusivity (RD). We used DTI to determine the integrity of the microstructure of the HT in ALL survivors. DESIGN: Case-control study. PATIENTS: Three groups were included: (i) 27 CRT treated ALL survivors on hormone supplementation, (ii) 17 CO-CP survivors on hormone supplementation but without HT involvement and (iii) 27 matched controls. MEASUREMENTS: DTI parameters of the HT were measured and body composition. RESULTS: Microstructural alterations in the HT were more severe in ALL survivors with a BMI ≥25 than with BMI <25. Compared to controls, ALL survivors had reduced FA (P=.04), increased MD (P<.001), AD (P<.001) and RD (P<.001) in the right and left HT. In the right HT, ALL survivors with a BMI ≥25 showed elevated MD (P=.03) and AD (P=.02) compared to ALL survivors with BMI <25. In contrast, DTI parameters did not differ between CP survivors and controls. CONCLUSIONS: Long-term follow-up after CRT for ALL DTI measures were affected in the HT despite complete hormone replacement. The present data suggest that ALL survivors have demyelination and axonal loss in the HT.
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Encéfalo/patologia , Craniofaringioma/patologia , Imagem de Tensor de Difusão/métodos , Hipotálamo/patologia , Leucemia/patologia , Adulto , Composição Corporal/fisiologia , Índice de Massa Corporal , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Fatores de RiscoRESUMO
Huntington's disease (HD) is a fatal neurodegenerative disorder caused by an expanded CAG repeat in the huntingtin (htt) gene. Neuropathology is most severe in the striatum and cerebral cortex. As mutant htt is ubiquitously expressed, it has not been possible to establish clear structure-to-function relationships for the clinical aspects. In the present study, we have injected recombinant adeno-associated viral vectors of serotype 5 (rAAV5) expressing an 853-amino-acid fragment of htt with either 79 (mutant) or 18 (wild-type) glutamines (Q) in the dorsal striatum of neonatal rats to achieve expression of htt in the forebrain. Rats were followed for 6 months and compared with control rats. Neuropathological assessment showed long-term expression of the green fluorescent protein (GFP) transgene (used as a marker protein) and accumulation of htt inclusions in the cerebral cortex with the rAAV5-htt-79Q vectors. We estimated that around 10% of NeuN-positive cells in the cerebral cortex and 2% of DARPP-32 neurons in the striatum were targeted with the GFP-expressing vector. Formation of intracellular htt inclusions was not associated with neuronal loss, gliosis or microglia activation and did not lead to altered motor activity or changes in body weight. However, the same mutant htt vector caused orexin loss in the hypothalamus - another area known to be affected in HD. In conclusion, our results demonstrate that widespread forebrain expression of mutant htt can be achieved using rAAV5-vectors and suggest that this technique can be further explored to study region-specific effects of mutant htt or other disease-causing genes in the brain.
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Dependovirus/genética , Modelos Animais de Doenças , Vetores Genéticos , Doença de Huntington/patologia , Proteínas do Tecido Nervoso/genética , Proteínas Nucleares/genética , Prosencéfalo/patologia , Ratos , Animais , Peso Corporal , Fator Neurotrófico Derivado do Encéfalo/análise , Fator Neurotrófico Derivado do Encéfalo/genética , Feminino , Glutamina/genética , Proteína Huntingtina , Doença de Huntington/genética , Doença de Huntington/fisiopatologia , Hipotálamo/química , Corpos de Inclusão/patologia , Peptídeos e Proteínas de Sinalização Intracelular/análise , Peptídeos e Proteínas de Sinalização Intracelular/genética , Masculino , Atividade Motora , Mutação , Proteínas do Tecido Nervoso/análise , Neuropeptídeos/análise , Neuropeptídeos/genética , Proteínas Nucleares/análise , Orexinas , Prosencéfalo/química , Prosencéfalo/fisiopatologia , Ratos Sprague-DawleyRESUMO
OBJECTIVE: Behavioral-variant frontotemporal dementia (bvFTD) is a progressive neurodegenerative brain disorder, clinically characterized by changes in cognition, personality, and behavior. Marked disturbances in eating behavior, such as overeating and preference for sweet foods, are also commonly reported. The hypothalamus plays a critical role in feeding regulation, yet the relation between pathology in this region and eating behavior in FTD is unknown. This study aimed to address this issue using 2 complementary approaches. METHODS: First, 18 early stage bvFTD patients and 16 healthy controls underwent high-resolution structural magnetic resonance imaging and assessment of eating behavior. Hypothalamic volumes were traced manually on coronal images. Second, postmortem analyses of 12 bvFTD cases and 6 matched controls were performed. Fixed hypothalamic tissue sections were stained for a cell marker and for peptides regulating feeding behaviors using immunohistochemistry. Stereological estimates of the hypothalamic volume and the number of neurons and glia were performed. RESULTS: Significant atrophy of the hypothalamus in bvFTD was present in both analyses. Patients with high feeding disturbance exhibited significant atrophy of the posterior hypothalamus. Neuronal loss, which was observed only in bvFTD cases with Tar DNA protein-43 deposition, was also predominant posteriorly. In contrast, orexin (hypocretin), neuropeptide Y, cocaine- and amphetamine-regulating transcript, and vasopressin-containing neurons that regulate appetite were spared in posterior nuclei known to participate in feeding regulation. INTERPRETATION: Degeneration and consequent dysregulation within the hypothalamus relates to significant feeding disturbance in bvFTD. These findings provide a basis for the development of therapeutic models.
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Comportamento Alimentar/fisiologia , Demência Frontotemporal/patologia , Hipotálamo/patologia , Idoso , Apetite/fisiologia , Atrofia/patologia , Contagem de Células , Feminino , Preferências Alimentares/fisiologia , Demência Frontotemporal/fisiopatologia , Humanos , Hipotálamo/fisiopatologia , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Neuroglia/patologia , Neurônios/patologia , Tamanho do ÓrgãoRESUMO
Neurodegenerative disorders (NDDs) such as Huntington's disease (HD) and the spectrum of amyotrophic lateral sclerosis (ALS) and frontotemporal dementia (FTD) are characterized by progressive loss of selectively vulnerable populations of neurons. Although often associated with motor impairments, these NDDs share several commonalities in early symptoms and signs that extend beyond motor dysfunction. These include impairments in social cognition and psychiatric symptoms. Oxytocin (OXT) is a neuropeptide known to play a pivotal role in the regulation of social cognition as well as in emotional behaviors such as anxiety and depression. Here, we present an overview of key results implicating OXT in the pathology of HD, ALS and FTD and seek to identify commonalities across these NDDs. OXT is produced in the hypothalamus, a region in the brain that during the past decade has been shown to be affected in HD, ALS, and FTD. Several studies using human post-mortem neuropathological analyses, measurements of cerebrospinal fluid, experimental treatments with OXT as well as genetic animal models have collectively implicated an important role of central OXT in the development of altered social cognition and psychiatric features across these diseases. Understanding central OXT signaling may unveil the underlying mechanisms of early signs of the social cognitive impairment and the psychiatric features in NDDs. It is therefore possible that OXT might have potential therapeutic value for early disease intervention and better symptomatic treatment in NDDs.
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Huntington disease (HD) is a fatal neurodegenerative disorder caused by expansion of a CAG repeat in the HD gene. Degeneration concentrating in the basal ganglia has been thought to account for the characteristic psychiatric symptoms, cognitive decline and motor dysfunction. However, the homeostatic control of emotions and metabolism are disturbed early in HD, and focused studies have identified a loss of orexin (hypocretin) neurons in the lateral hypothalamus in HD patients. There has been limited assessment of other hypothalamic cell populations that may be involved. In this study, we quantified the neuropeptide-expressing hypothalamic neurons known to regulate metabolism and emotion in patients with HD compared to healthy controls using unbiased stereological methods. We confirmed the loss of orexin-expressing neurons in HD and revealed substantial differences in the peptide expression of other neuronal populations in the same patients. Both oxytocin- and vasopressin-expressing neurons were decreased by 45 and 24%, respectively, while the number of cocaine- and amphetamine-regulated transcript (CART)-expressing neurons was increased by 30%. The increased expression of CART in the hypothalamus is consistent with a previous study showing increased CART levels in cerebrospinal fluid from HD patients. There was no difference in the numbers of neuropeptide Y-expressing neurons. These results show significant and specific alterations in the peptide expression of hypothalamic neurons known to regulate metabolism and emotion. They may be important in the development of psychiatric symptoms and metabolic disturbances in HD, and may provide potential targets for therapeutic interventions.
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Doença de Huntington/metabolismo , Doença de Huntington/patologia , Hipotálamo/metabolismo , Hipotálamo/patologia , Neuropeptídeos/metabolismo , Humanos , Doença de Huntington/diagnóstico , Degeneração Neural/diagnóstico , Degeneração Neural/metabolismo , Degeneração Neural/patologia , Neurônios/metabolismo , Neurônios/patologiaRESUMO
Semaglutide, a glucagon-like peptide 1 (GLP-1) analog, induces weight loss, lowers glucose levels, and reduces cardiovascular risk in patients with diabetes. Mechanistic preclinical studies suggest weight loss is mediated through GLP-1 receptors (GLP-1Rs) in the brain. The findings presented here show that semaglutide modulated food preference, reduced food intake, and caused weight loss without decreasing energy expenditure. Semaglutide directly accessed the brainstem, septal nucleus, and hypothalamus but did not cross the blood-brain barrier; it interacted with the brain through the circumventricular organs and several select sites adjacent to the ventricles. Semaglutide induced central c-Fos activation in 10 brain areas, including hindbrain areas directly targeted by semaglutide, and secondary areas without direct GLP-1R interaction, such as the lateral parabrachial nucleus. Automated analysis of semaglutide access, c-Fos activity, GLP-1R distribution, and brain connectivity revealed that activation may involve meal termination controlled by neurons in the lateral parabrachial nucleus. Transcriptomic analysis of microdissected brain areas from semaglutide-treated rats showed upregulation of prolactin-releasing hormone and tyrosine hydroxylase in the area postrema. We suggest semaglutide lowers body weight by direct interaction with diverse GLP-1R populations and by directly and indirectly affecting the activity of neural pathways involved in food intake, reward, and energy expenditure.
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Peso Corporal/efeitos dos fármacos , Encéfalo/efeitos dos fármacos , Peptídeos Semelhantes ao Glucagon/farmacologia , Vias Neurais/efeitos dos fármacos , Animais , Ingestão de Alimentos/efeitos dos fármacos , Metabolismo Energético/efeitos dos fármacos , Receptor do Peptídeo Semelhante ao Glucagon 1/efeitos dos fármacos , Camundongos , RatosRESUMO
Huntington's disease (HD) is a fatal genetic neurodegenerative disorder. It has mainly been considered a movement disorder with cognitive symptoms and these features have been associated with pathology of the striatum and cerebral cortex. Importantly, individuals with the mutant huntingtin gene suffer from a spectrum of non-motor features often decades before the motor disorder manifests. These symptoms and signs include a range of psychiatric symptoms, sleep problems and metabolic changes with weight loss particularly in later stages. A higher body mass index at diagnosis is associated with slower disease progression. The common psychiatric symptom of apathy progresses with the disease. The fact that non-motor features are present early in the disease and that they show an association to disease progression suggest that unravelling the underlying neurobiological mechanisms may uncover novel targets for early disease intervention and better symptomatic treatment. The hypothalamus and the limbic system are important brain regions that regulate emotion, social cognition, sleep and metabolism. A number of studies using neuroimaging, postmortem human tissue and genetic manipulation in animal models of the disease has collectively shown that the hypothalamus and the limbic system are affected in HD. These findings include the loss of neuropeptide-expressing neurons such as orexin (hypocretin), oxytocin, vasopressin, somatostatin and VIP, and increased levels of SIRT1 in distinct nuclei of the hypothalamus. This review provides a summary of the results obtained so far and highlights the potential importance of these changes for the understanding of non-motor features in HD.
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Sintomas Comportamentais , Doença de Huntington , Hipotálamo , Doenças Metabólicas , Animais , Sintomas Comportamentais/etiologia , Sintomas Comportamentais/fisiopatologia , Humanos , Doença de Huntington/complicações , Doença de Huntington/metabolismo , Doença de Huntington/patologia , Hipotálamo/metabolismo , Hipotálamo/patologia , Doenças Metabólicas/etiologia , Doenças Metabólicas/metabolismoRESUMO
Light Sheet Fluorescence Microscopy (LSFM) of whole organs, in particular the brain, offers a plethora of biological data imaged in 3D. This technique is however often hindered by cumbersome non-automated analysis methods. Here we describe an approach to fully automate the analysis by integrating with data from the Allen Institute of Brain Science (AIBS), to provide precise assessment of the distribution and action of peptide-based pharmaceuticals in the brain. To illustrate this approach, we examined the acute central nervous system effects of the glucagon-like peptide-1 (GLP-1) receptor agonist liraglutide. Peripherally administered liraglutide accessed the hypothalamus and brainstem, and led to activation in several brain regions of which most were intersected by projections from neurons in the lateral parabrachial nucleus. Collectively, we provide a rapid and unbiased analytical framework for LSFM data which enables quantification and exploration based on data from AIBS to support basic and translational discovery.
Assuntos
Mapeamento Encefálico , Hipoglicemiantes/farmacologia , Liraglutida/farmacologia , Sistema Nervoso/efeitos dos fármacos , Animais , Tronco Encefálico/metabolismo , Tronco Encefálico/patologia , Ingestão de Alimentos , Receptor do Peptídeo Semelhante ao Glucagon 1/agonistas , Hipotálamo/metabolismo , Hipotálamo/patologia , Camundongos , Camundongos Endogâmicos C57BL , Microscopia de Fluorescência , Sistema Nervoso/metabolismo , Proteínas Proto-Oncogênicas c-fos/metabolismoRESUMO
Subjective reports of sleep disturbance are a common feature of Huntington's disease (HD); however, there is limited research investigating the relationship between sleep problems with changes in brain and behaviour. This study aimed to investigate whether subjective reports of sleep problems in HD are associated with brain volume, neurocognitive decline, and neuropsychiatric symptoms. This retrospective pilot study used brain volume, neurocognitive and neuropsychiatric data from premanifest (pre-HD) and symptomatic HD (symp-HD). Subjective sleep problem was measured using the sleep item of the Beck's Depression Inventory-II (BDI-II). Pre-HD individuals reporting sleep problems had significantly poorer neuropsychiatric outcomes compared to those not reporting sleep problems. In the symp-HD group, those with sleep problems had significantly accelerated thalamic degeneration and poorer neuropsychiatric outcomes compared to those without sleep problems. There was no relationship between subjective sleep problems and neurocognitive measures. These findings suggest an association between subjective sleep disturbance, neuropathology, and development of neuropsychiatric symptoms in HD. Further studies using quantitative EEG-based monitoring of sleep in HD and changes in the brain and behaviour will be necessary to establish the causal nature of this relationship.
Assuntos
Encéfalo/diagnóstico por imagem , Transtornos Cognitivos/etiologia , Doença de Huntington/complicações , Transtornos do Sono-Vigília/etiologia , Adulto , Transtornos Cognitivos/diagnóstico por imagem , Estudos Transversais , Feminino , Humanos , Doença de Huntington/diagnóstico por imagem , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Testes Neuropsicológicos , Projetos Piloto , Escalas de Graduação Psiquiátrica , Estudos Retrospectivos , Transtornos do Sono-Vigília/diagnóstico por imagem , Tálamo/diagnóstico por imagemRESUMO
Metabolic complications are prevalent in individuals treated with cranial radiotherapy (CRT) for childhood acute lymphoblastic leukemia (ALL). The hypothalamus is a master regulator of endocrine and metabolic control. The aim of this study was to investigate whether the hypothalamic volume would be associated to metabolic parameters in ALL survivors. Thirty-eight (21 women) survivors participated in this study 34 years after diagnosis and with a median age of 38 (27-46) years. All were treated with a median CRT dose of 24 Gy and 11 years (3-13) of complete hormone supplementation. Comparisons were made to 31 matched controls. We performed analyses of fat mass, fat free mass, plasma (p)-glucose, p-insulin, Homa-Index (a measure of insulin resistance), serum (s)-leptin, s-ghrelin and of the hypothalamic volume in scans obtained by magnetic resonance imaging (MRI) at 3 Tesla. Serum leptin/kg fat mass (r = -0.4, P = 0.04) and fat mass (r = -0.4, P = 0.01) were negatively correlated with the HT volume among ALL survivors, but not among controls. We also detected significantly higher BMI, waist, fat mass, p-insulin, Homa-Index, leptin/kg fat mass and s-ghrelin and significantly lower fat free mass specifically among female ALL survivors (all P<0.01). Interestingly, s-ghrelin levels increased with time since diagnosis and with low age at diagnosis for childhood ALL. Our results showed that leptin/kg fat mass and fat mass were associated with a reduced HT volume 34 years after ALL diagnosis and that women treated with CRT after ALL are at high risk of metabolic abnormalities. Taken together our data suggest that the hypothalamus is involved in the metabolic consequences after CRT in ALL survivors.
Assuntos
Irradiação Craniana , Terapia de Reposição Hormonal , Hipotálamo/metabolismo , Hipotálamo/efeitos da radiação , Leucemia-Linfoma Linfoblástico de Células Precursoras/sangue , Sobreviventes , Adulto , Glicemia/metabolismo , Composição Corporal , Índice de Massa Corporal , Estudos de Casos e Controles , Feminino , Grelina/sangue , Hormônio do Crescimento/uso terapêutico , Humanos , Hipotálamo/efeitos dos fármacos , Hipotálamo/patologia , Insulina/sangue , Resistência à Insulina , Leptina/sangue , Estudos Longitudinais , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Leucemia-Linfoma Linfoblástico de Células Precursoras/tratamento farmacológico , Leucemia-Linfoma Linfoblástico de Células Precursoras/patologia , Leucemia-Linfoma Linfoblástico de Células Precursoras/radioterapia , RiscoRESUMO
Huntington disease (HD) is a fatal neurodegenerative disorder caused by an expanded CAG repeat in the huntingtin gene. Non-motor symptoms and signs such as psychiatric disturbances, sleep problems and metabolic dysfunction are part of the disease manifestation. These aspects may relate to changes in the hypothalamus, an area of the brain involved in the regulation of emotion, sleep and metabolism. Neuropathological and imaging studies using both voxel-based morphometry (VBM) of magnetic resonance imaging (MRI) as well as positron emission tomography (PET) have demonstrated pathological changes in the hypothalamic region during early stages in symptomatic HD. In this investigation, we aimed to establish a robust method for measurements of the hypothalamic volume in MRI in order to determine whether the hypothalamic dysfunction in HD is associated with the volume of this region. Using T1-weighted imaging, we describe a reproducible delineation procedure to estimate the hypothalamic volume which was based on the same landmarks used in histologically processed postmortem hypothalamic tissue. Participants included 36 prodromal HD (pre-HD), 33 symptomatic HD (symp-HD) and 33 control participants who underwent MRI scanning at baseline and 18 months follow-up as part of the IMAGE-HD study. We found no evidence of cross-sectional or longitudinal changes between groups in hypothalamic volume. Our results suggest that hypothalamic pathology in HD is not associated with volume changes.
Assuntos
Doença de Huntington/diagnóstico por imagem , Hipotálamo/diagnóstico por imagem , Tomografia por Emissão de Pósitrons , Adulto , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Tamanho do Órgão , RadiografiaRESUMO
Huntington's disease (HD) is a neurodegenerative disorder caused by an expanded CAG repeat in the huntingtin gene. Today, the clinical diagnosis of the disease requires unequivocal signs of typical motor disturbances, which is thought to be due to pathology in the striatum of the basal ganglia. Increasing numbers of studies have emphasized that also non-motor symptoms and signs are common and occur early in HD. These include psychiatric disturbances and cognitive impairment as well as sleep disturbances with disrupted circadian rhythm, autonomic dysfunction and metabolic changes. Several of the non-motor features may be results of dysfunction of the hypothalamus and the limbic system, which are interconnected structures central in the regulation of emotion, sleep and metabolism. In fact, recent studies using postmortem tissue, magnetic resonance imaging and positron emission tomography have shown that hypothalamic and limbic system changes occur early in clinical HD. This review summarizes the current state of knowledge in this area based on clinical studies as well as experiments in animal models of the disease and establishes that hypothalamic and limbic system changes are part of the HD pathology.